Percussion musical instruments capable of creating a rhythm are known in the art. Shakers are one type of percussion instrument capable of generating a rhythmic pattern of sound by moving the shaker back and forth. Prior art shakers typically comprise a striker material freely disposed in an enclosed shaker body. Although a percussionist may obtain different sound patterns while operating such a shaker, it is difficult for the percussionist to produce different sounds and different rhythms using a single shaker. In addition, it is difficult for the percussionist to control the rhythmic patterns and tempos.